[PATCH v3 0/6] arm64: qcom: allow up to 4 lanes for the Type-C DisplayPort Altmode

Alex alex.vinarskis at gmail.com
Thu May 29 04:13:42 PDT 2025


On 5/27/25 22:40, Konrad Dybcio wrote:
> Register a typec mux in order to change the PHY mode on the Type-C
> mux events depending on the mode and the svid when in Altmode setup.
>
> The DisplayPort phy should be left enabled if is still powered on
> by the DRM DisplayPort controller, so bail out until the DisplayPort
> PHY is not powered off.
>
> The Type-C Mode/SVID only changes on plug/unplug, and USB SAFE states
> will be set in between of USB-Only, Combo and DisplayPort Only so
> this will leave enough time to the DRM DisplayPort controller to
> turn of the DisplayPort PHY.
>
> The patchset also includes bindings changes and DT changes.
>
> This has been successfully tested on an SM8550 board, but the
> Thinkpad X13s deserved testing between non-PD USB, non-PD DisplayPort,
> PD USB Hubs and PD Altmode Dongles to make sure the switch works
> as expected.
>
> The DisplayPort 4 lanes setup can be check with:
> $ cat /sys/kernel/debug/dri/ae01000.display-controller/DP-1/dp_debug
> 	name = msm_dp
> 	drm_dp_link
> 		rate = 540000
> 		num_lanes = 4
> ...


Hi,


Thanks for the respin. Together with `mode-switch;` for x1e80100.dtsi 
and 4 lane DP change in respective .dts, successfully tested on Asus 
Zenbook A14 (Parade PS8833 on both Type-C ports).

Tested with:

- Type-C USB3.0 pendrive

- Type-C to DP cable (x4 DP lanes)

- Type-C to HDMI/USB/... dongle (x2 USB3, x2 DP)

All three variants work, in both orientations, on both ports. When 
switching from x4 DP lanes cable to USB3 pendrive no re-plug was needed, 
it works right away. Suspend and resume (to my surprise) also works.


Tested-by: Aleksandrs Vinarskis <alex.vinarskis at gmail.com> # x1e80100, 
ps8833


Regards,

Alex


>
> This patchset depends on [1] to allow broadcasting the type-c mode
> to the PHY, otherwise the PHY will keep the combo state while the
> retimer would setup the 4 lanes in DP mode.
>
> [1] https://lore.kernel.org/all/20240527-topic-sm8x50-upstream-retimer-broadcast-mode-v1-0-79ec91381aba@linaro.org/
> Changes in v3:
> - Take the series from Neil
> - Rebase
> - Rename many variables
> - Test on X1E & X13s
> - Apply a number of small cosmetic/codestyle changes
> - Remove some unused variables
> - Some smaller bugfixes
> - Link to v2: https://lore.kernel.org/lkml/20240527-topic-sm8x50-upstream-phy-combo-typec-mux-v2-0-a03e68d7b8fc@linaro.org/
> Changes in v2:
> - Reference usb-switch.yaml in bindings patch
> - Fix switch/case indenting
> - Check svid for USB_TYPEC_DP_SID
> - Fix X13s patch subject
> - Update SM8650 patch to enable 4 lanes on HDK aswell
> - Link to v1: https://lore.kernel.org/r/20240229-topic-sm8x50-upstream-phy-combo-typec-mux-v1-0-07e24a231840@linaro.org
>
> Signed-off-by: Konrad Dybcio <konrad.dybcio at oss.qualcomm.com>
> ---
> Konrad Dybcio (1):
>        phy: qcom: qmp-combo: Rename 'mode' to 'phy_mode'
>
> Neil Armstrong (5):
>        dt-bindings: phy: qcom,sc8280xp-qmp-usb43dp: Reference usb-switch.yaml to allow mode-switch
>        phy: qcom: qmp-combo: store DP phy power state
>        phy: qcom: qmp-combo: introduce QMPPHY_MODE
>        phy: qcom: qmp-combo: register a typec mux to change the QMPPHY_MODE
>        arm64: dts: qcom: sc8280xp-lenovo-thinkpad-x13: Set up 4-lane DP
>
>   .../phy/qcom,sc8280xp-qmp-usb43dp-phy.yaml         |   7 +-
>   .../dts/qcom/sc8280xp-lenovo-thinkpad-x13s.dts     |   6 +-
>   drivers/phy/qualcomm/phy-qcom-qmp-combo.c          | 182 +++++++++++++++++++--
>   3 files changed, 173 insertions(+), 22 deletions(-)
> ---
> base-commit: 460178e842c7a1e48a06df684c66eb5fd630bcf7
> change-id: 20250527-topic-4ln_dp_respin-c6924a8825ce
>
> Best regards,



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